The trainee's career goals are to: 1) become a dental academician and an independent researcher;2) develop the skill-set needed to design, conduct, and analyze complex clinically relevant research projects that pertain to periodontal diseases and 3) develop the expertise to translate this information, as a dental educator, to dental students and post-graduate students. These goals, while ambitious are achievable through the career development program outlined by the trainee, with valuable input from his mentors and co-mentors at SBU-School of Dental Medicine and the GCRC at SBU-Hospital. Through the trainees'initiative, he was recently awarded a Minority Dental Faculty Development Award, administered through ADEA, one of 3 individuals to receive this award in New York State. This will enable him to start the PhD program while developing this research and career development program. It is now known that more than one in three people over age 30 have periodontitis;and, by a conservative estimate, 35.7 million people in the United States have periodontitis. Despite this, we still understand very little about the inflammatory processes in gingivitis and chronic periodontitis. That is, what is the specific role that the innate and adaptive arms of the immune response play in the development of gingivitis and in resolution of periodontitis? The mentor is a well-established investigator and expert in the immunopathogenesis of periodontal disease, who directs the Periodontal Molecular Immunology Laboratory and trains graduate students, residents and dental students. The trainee has developed, in conjunction with the mentor, a novel overall hypothesis and approach to understanding the pathophysiology of gingivitis and chronic periodontitis (CP). Presently lacking is precisely defined human clinical studies in which to test these innovative concepts. The proposed studies will establish the dendritic cell (DC) subpopulations that traffic into the gingiva and the chemokines/chemokine receptors that are expressed in experimental gingivitis (Specific Aim 1) and in chronic periodontitis (CP) before and after disease treatment (Specific Aim 2). It is anticipated that the results of these human clinical studies should further elucidate the mechanisms that are involved in the pathogenesis of gingivitis and CP. Moreover, we anticipate that these studies will facilitate the identification of surrogate markers of gingivitis/CP.